A high output amplifier (HPA) having high efficiency generally has input/output characteristics with low linearity. When power is amplified using such amplifier, the desired output may not be obtained due to distortion of input/output characteristics. Thus, in order to compensate for the distortion of the amplifier, a distortion compensation circuit that obtains the desired amplifier output by performing a distortion compensation process for generating an inverse distortion characteristic, which is inverse to the distortion characteristic of the amplifier, through digital signal processing on an input signal of the amplifier and adding the inverse distortion characteristics to the input of the amplifier has been proposed (for example, refer to non-patent document 1).    Non-Patent Document 1: Thesis by Lei Ding, “Digital predistortion of power amplifiers for wireless application”, Georgia institute of Technology, March 2004